In this 2010 photo provided by the Massachusetts Bay Transportation Authority, Richard Donohue Jr., left, and Sean Collier pose together for a photo at their graduation from the Municipal Police Officers' Academy. On Thursday, April 18, 2013, Massachusetts Institute of Technology Police Officer Collier was fatally shot on the MIT campus, and transit police officer Donohue was shot and critically wounded. Authorities allege that Boston Marathon bombing suspects Tamerlan and Dzhokhar Tsarnaev were responsible. (AP Photo/Massachusetts Bay Transportation Authority)
(The Associated Press)

CAMBRIDGE, Mass. – Doctors say the Boston transit police officer wounded in a shootout with the marathon bombing suspects had lost nearly all his blood and his heart had stopped from a single gunshot wound that severed three major blood vessels in his right thigh.

Surgeons at Mount Auburn Hospital in Cambridge say 33-year-old Richard Donohue is in stable but critical condition. He is sedated and on a breathing machine but opened his eyes, moved his hands and feet and squeezed his wife's hand Sunday.

Emergency workers started CPR on the scene to restart his heart. Doctors say he is expected to make a full recovery and that nerves and muscles in his leg are intact.

Transit officials say Donohue had gotten out of his cruiser and was shooting at the suspects when he was hit.